Tool turret

ABSTRACT

A tool turret, with a base body ( 1 ) which is attached or is to be attached to a machine tool and which defines a turret axis ( 13 ) around which the tool disk ( 7 ) is pivoted on the base body ( 1 ) and which disk has a plurality of tool stations ( 45 ) which are distributed on its periphery and which, by turning the tool disk ( 7 ), can be set into at least one working position at a time, in which a tool drive ( 31, 35 ), located within the tool disk ( 7 ) with its output-side gear part ( 35 ) which can be turned around an axis of rotation which is radial to the turret axis ( 13 ), by coupling engages the tool-side coupling part for driving at least one tool which is located on the tool station ( 45 ) which is aligned to the working position, is characterized in that the output-side gear part ( 35 ) is located in the tool disk ( 7 ) to be pivotable around the turret axis ( 13 ), and that in the tool disk ( 7 ) there is a clutch ( 47 ) which can be switched between a first operating position in which the output-side gear part ( 35 ) for pivoting motion around the turret axis ( 13 ) is connected to the tool disk ( 7 ), and a second operating position in which the output-side gear part ( 35 ) is decoupled from the tool disk ( 7 ).

The invention relates to a tool turret, with a base body which is attached or is to be attached to a machine tool and which defines a turret axis around which the tool disk is pivoted on the base body and which disk has a plurality of tool stations which are distributed on its periphery and which, by turning the tool disk, can be set into at least one working position at a time, in this position a tool drive, located within the tool disk, with its output-side gear part which can be turned around an axis of rotation which is radial to the turret axis, by coupling engages the tool-side coupling part for driving at least one tool which is located on the tool station which is aligned to the working position, the output-side gear part being mounted in the tool disk so as to be pivotable around the turret axis.

DE 689 08 208 T2 or DE 10 2005 033 890 A1 discloses tool turrets which are intended for use in machine tools such as lathes, machining centers and similar devices. When using such tool turrets, the tools which are to be used and which are located on the tool stations of the tool disk are both stationary tools such as cutting tools and the like, as well as so-called rotary tools for machining process such as drilling, milling and the like. In this case, rotary driving for the pertinent rotary tool located on the tool station which is in the working position takes place by way of an internal tool drive whose output-side gear part can be engaged by coupling by the pertinent, tool-side coupling part when the tool station to which the rotary tool is attached is in a defined working position.

Fixing the angular setting of this defined working position relative to the base body is disadvantageous in some cases. While in rotary machining a fixed angular setting of the working position is advantageous because metal cutting is always done centered on the workpiece axis, it is also often desirable to be able to perform drilling or milling even outside of the fixed angular setting, with the feed or machining direction not being at a right angle to the workpiece axis.

DE 39 29 803 C1 discloses a generic tool turret, in particular for automatic lathes, with tool holders for tools which can be driven in rotation. In the known solution a turret head on a turret body is pivoted around the turret axis and can be locked in several working positions. At least one tool holder is interchangeably attached to the turret head and has a rotary clamping device for a tool and a spindle for driving the clamping device with a gear wheel located within the turret head. In the turret head a drive shaft which is parallel to the turret axis is movably mounted axially and can be loaded with a hydraulically generated axial force. The drive shaft bears a gear wheel by means of which the spindle can be driven in one working position of the turret head. The drive shaft is pretensioned with a small axial force for purposes of starting the two gear wheels and only after engaging the two gear wheels can it be fixed in the axial direction with hydraulically generated force.

DE 28 49 167 B2 shows a generic tool turret solution which is comparable to the aforementioned solution. There is no clutch within the tool disk in the known generic solutions.

Proceeding from this prior art, the object of the invention is to make available a tool turret with which machining processes can be carried out by means of rotary tools not only when the tool disk is set to a defined working position, but also in those cases in which the tool disk is in any desired rotary position.

According to the invention, this object is achieved by a tool turret with the features of claim 1 in its entirety.

According to the characterizing part of claim 1, one essential particularity of the invention consists in that in the tool disk there is a clutch which makes it possible to couple the output-side gear part for a pivoting motion around the turret axis to the tool disk. Thus the output-side gear part in the corresponding operating position of the clutch, when the tool disk is being turned into the desired rotary position, can be entrained by the tool disk, which makes it possible to work with rotary tools in the desired different angular positions. On the other hand, in the pertinent operating position of the clutch, the output-side gear part can be decoupled from the tool disk, furthermore making it possible to move another tool into the working position. If the output-side gear part, with which a rotary tool to be driven engages its tool-side coupling part, is located in the tool disk to be pivotable around the turret axis, in different angular positions it can form the drive for the respective rotary tool.

In preferred embodiments, the clutch as a movable coupling part has a bushing which forms a rotary support of the output-side gear part for its rotation around the radial axis of rotation, is arranged to be able to move radially between a first operating position and a second operating position in the tool disk and, in the first operating position, assumes a radially advanced position in which with radially end-side drivers it engages the driver surfaces of the tool disk. The double function of the bushing both for supporting the output-side gear part of the tool drive and also as the movable coupling part of the clutch leads to an extremely compact construction in which the tool drive and the clutch can be housed without difficulty within the installation space available in the tool disk.

In especially advantageous embodiments which are characterized by an especially simple and compact design, the output-side gear part as a further component of the clutch together with the bushing can be radially moved in the tool disk such that in the second operating position it assumes a position which is shifted radially to the inside and in which it is secured on the base body against pivoting motion around the turret axis, but can be turned around its radial axis of rotation. In interaction with the base body thus a defined initial angular position for machining processes both with stationary tools and also with rotary tools is established when the clutch is in the second operating position. Rotary motions of the tool disk for adjustment purposes can be undertaken here without the output-side gear part of the tool drive being entrained out of this defined initial position. If, on the other hand, the clutch is transferred into the first operating position, the output-side gear part can in turn be entrained with the rotary motion of the tool disk into the desired position in which the rotary tool is to be operated.

The tool drive can be designed as an angle drive with a drive-side crown gear which is rotatable around the turret axis, with teeth which lie in the radial plane, whose radial extension is chosen such that the teeth of the output-side gear part in its radial displacements between the first and second operating position permanently engage the teeth of the crown gear. The tool drive can therefore be active regardless of the operating position the clutch is in.

The arrangement is preferably such that the base body has a central support column which defines the turret axis and around which the tool disk is pivoted, within the latter there being a guide body on which the movable components of the clutch, such as the bushing and the output-side gear part which is pivoted in it, are guided both for radial movements between the operating positions and also for pivoting movements around the turret axis.

Especially little installation space is required here, if the clutch can be transferred into the operating positions using a hydraulic medium, preferably by means of hydraulic actuation.

In this case the arrangement can be such that the bushing on the outer peripheral side has a projecting ring body which as a moveable annular piston separates from one another the pressure chambers which are made on the guide body in the guide section on which the bushing is guided for the displacement motions between the operating positions, and the pressure chambers can be selectively supplied with hydraulic medium in order to transfer the clutch into the operating positions by movement of the bushing.

Preferably the drive-side crown gear of the tool drive is mounted on a hollow shaft which surrounds the support column, the arrangement preferably being made such that on the end region of the hollow shaft which is adjacent to that end of the support column which is away from the tool disk, a pinion which sits on the hollow shaft is geared to the output gear of the drive motor.

The drive for the rotary motion of the tool disk around the turret axis can be a torque motor which is located coaxially to it and whose rotor is connected to the tool disk for direct driving of it.

In order to fix the tool disk in the desired adjustment position without slip, between the base body and the tool disk there is preferably a clamping mechanism, preferably actuation taking place hydraulically.

The invention is detailed below using one embodiment shown in the drawings.

FIG. 1 shows a longitudinal section of the tool turret which has been slightly schematically simplified according to one embodiment of the invention and

FIGS. 2 and 3 show cutaways, enlarged and schematically simplified, looking at the interior of only the tool disk of the embodiment, FIG. 2 showing the clutch in the first operating position and FIG. 3 showing the clutch in the second operating position.

The embodiment of the tool turret shown in the drawings has a base body 1 with a turret housing 3 which on one end is closed with a housing cover 5 and whose other end is connected to the tool disk 7. On the housing cover 5 an electric drive motor 9 is flanged, of which only a partial section adjoining its output shaft 8 is shown. On the housing cover 5, moreover, a support column 11 which forms part of the base body 1 is attached with its one end, whose other end extends into the interior of the tool disk 7. The support column 11 defines the turret axis 13 around which the tool disk 7 is pivoted on the base body 1. In order to fix the tool disk 7 in selected rotary positions without slip relative to the base body 1, between the bordering flat surfaces of the base body 1 and the tool disk 7, specifically, on the turret housing 3 and on the tool disk 7, a clamping mechanism 15, which is shown schematically simplified only in FIG. 1, is installed and can be clamped hydraulically as is conventional for these devices; this is not detailed in FIG. 1. For setting the angular positions of the tool disk 7 around the turret axis 13 there is a torque motor 21 which concentrically surrounds the support column 11, whose outer rotor 19 is connected to the tubular body 17 of the tool disk 7 which extends into the interior of the turret housing 3. The inside stator of the motor 21 whose stator winding is designated as 23 is connected to the turret housing 3 for rotation.

The rotary actuator for a tool drive located within the tool disk 7 is a hollow shaft 25 which surrounds the support column 11; on its end adjacent to the housing cover 5 sits a drive pinion 27, and, accordingly, the hollow shaft 25 itself, which are supported on the housing cover 5 by way of an antifriction bearing 29. The pinion 27 with its teeth engages the pinion gear 29 on the output shaft 8 of the motor 9. On the other end of the hollow shaft 25 there is a crown gear 31, and, accordingly, the hollow shaft 25 itself, which are supported on the guide body 61 by way of another antifriction bearing 33.

The crown gear 31 forms the drive-side part of the tool drive located within the tool disk 7. Its details and the details about the clutch which is located within the tool disk can be more clearly taken from FIGS. 2 and 3. The output-side gear part which interacts with the crown gear 31 is a body of revolution 35 with a shaft 37 which is concentric to its axis of rotation and which forms a rotary coupling part 39 with which a tool-side coupling part for the rotary actuator of a rotary tool which is not shown and which is located on one tool station 45 in a tool holder 44. On its end opposite the shaft part 37 the body of revolution 35 forms an outside gear rim 41 which concentrically surrounds the axis of rotation and which engages the teeth 43 of the crown gear 31. The teeth 43 on the crown gear 31 in the radial plane has an extension which is chosen such that the gear rim 41 is permanently engaged with the teeth 43, regardless of whether the body of revolution 35 is radially set by a radial displacement motion into a position which corresponds to the first operating position or a position which corresponds to the second operating position of the clutch. FIGS. 1 and 2 each show the body of revolution 35, i.e., the output-side gear part of the tool drive in the radial position which corresponds to the first operating position of the clutch, while FIG. 3 shows the body of revolution 35 in the radial setting position which corresponds to the second operating position of the clutch. In both positions the gear rim 41 with its teeth engages the teeth 43 of the crown gear 31.

The clutch itself as the coupling part which can move radially between the first and second operating position has a bushing 47 which concentrically surrounds the shaft 37 of the body of revolution 35 and forms a pivoted support of the body of revolution 35 which forms the output-side gear part. On the antifriction bearing 49 which is away from the turret axis 13 the bushing 47 has a shaft locking ring 51 by way of which the bushing 47 entrains the body of revolution 35 in a displacement motion directed radially to the outside into the first operating position. In displacement motions of the bushing 47 radially to the inside into the second operating position of the clutch, the bushing 47 entrains the body of revolution 35 by contact of the bearing 49 with the stepped surface 70 of the bushing 47.

In the embodiment shown here, actuation of the clutch takes place hydraulically. For this purpose, the bushing 47 on the outer peripheral side has a projecting ring body 53 which acts as an annular piston which is guided in an annular guide section 55, and in it forms a separating element between the first pressure chamber 57 (FIGS. 1 and 2) and the second pressure chamber 59 (FIG. 3). The guide section 55 is guided for pivoting motions around the turret axis 13 on a guide body 61 in the tool disk 7.

FIGS. 1 and 2 show the clutch in the first operating position in which the pressure chamber 57 is supplied with a hydraulic medium so that the bushing 47 has moved radially to the outside into the position in which the end-side drivers 63 lock the bushing 47 on the driver surfaces 65 of the tool disk 7. In this operating position the body of revolution 35 which is used as the output-side gear part with its gear rim 41 is moved radially away from the support column 11, but remains with its gear rim 41 by its teeth engaged with the teeth 43 of the crown gear 31 so that a rotary tool which is held in the tool mounting 44 can be driven. A machining process can therefore be carried out with the pertinent rotary tool, regardless of in which rotary position the tool station 45 is set on which the tool mounting 44 of the pertinent rotary tool is located, by turning the tool disk 7.

FIG. 3, on the other hand, shows the positions which correspond to the second operating position of the clutch, at this point the other pressure chamber 59 being supplied with hydraulic fluid so that the ring body 53 of the bushing 47 which is used as an annular ring piston and, accordingly, the bushing itself are moved radially to the inside. In this position the drivers 63 of the bushing 47 are pulled back from the driver surfaces 65 of the tool disk 7. Pivoting motions of the latter around the turret axis 13 therefore do not lead to entrainment of the body of revolution 35 which forms the output-side gear part of the tool drive. The tool drive therefore remains in a given position regardless of the rotary setting motions of the tool disk 7.

So that the guide body 61 is securely fixed in the rotary setting motion of the tool disk 7 in its angle position relative to the turret axis 13, the body of revolution 35 in the position pushed to the inside, i.e., the second operating position of the clutch, must be fixed in a defined initial position, i.e., in the position which is preferred for operation of the rotary tool. This takes place such that in the position pushed to the inside a flattened part 71 of the body of revolution 35 presses through a passage 69 of the guide body 61 onto the flattened end sections 72 of the support column 11 and thus is fixed against rotation on the support column 11. At this juncture, in the position of the body of revolution 35 pushed radially to the inside, i.e., the second operating position of the clutch, the body of revolution 35 must be fixed in a defined initial position, i.e., in a position which is preferred for operation of the rotary tool. In this configuration the transfer of the clutch into the second operating position presupposes exact alignment of the tool drive, i.e., of the body of revolution 35, into a defined rotary position. It goes without saying that there are position sensors which are not shown and which correspond to prior art for controlling these operating functions both with respect to the control of operating functions of the clutch and also the setting of the rotary positions of the tool disk 7. 

1. A tool turret, with a base body (1) which is attached or is to be attached to a machine tool and which defines one turret axis (13) around which the tool disk (7) is pivoted on the base body (1) and which disk has a plurality of tool stations (45) which are distributed on its periphery and which, by turning the tool disk (7), can be set into at least one working position at a time, in which a tool drive (31, 35), located within the tool disk (7) with its output-side gear part (35) which can be turned around an axis of rotation which is radial to the turret axis (13), by coupling engages the tool-side coupling part for driving at least one tool which is located on the tool station (45) which is aligned to the working position, the output-side gear part (35) being mounted in the tool disk (7) so as to be pivotable around the turret axis (13), characterized in that in the tool disk (7) there is a clutch (47) which can be switched between a first operating position in which the output-side gear part (35) for pivoting motion around the turret axis (13) is connected to the tool disk (7), and a second operating position in which the output-side gear part (35) is decoupled from the tool disk (7).
 2. The tool turret according to claim 1, characterized in that the clutch as a movable coupling part has a bushing (47) which forms a rotary support of the output-side gear part (35) for its rotation around the radial axis of rotation, is arranged to be able to move radially between a first operating position and a second operating position in the tool disk (7) and in the first operating position assumes a radially advanced position in which with radially end-side drivers (63) it engages the driver surfaces (65) of the tool disk (7).
 3. The tool turret according to claim 2, characterized in that the output-side gear part (35) as a further component of the clutch together with the bushing (47) can be radially moved in the tool disk (7) and in the second operating position assumes a position which is shifted radially to the inside and in which it is secured on the base body (1) against pivoting motion around the turret axis (13).
 4. The tool turret according to claim 3, characterized in that the tool drive is designed as an angle drive with a drive-side crown gear (31) which can be turned around the turret axis (13), with teeth (43) which lie in the radial plane, whose radial extension is chosen such that the output-side gear part (35) with its teeth (41) in radial displacements between the first and second operating position remains permanently engaged with the teeth (43) of the crown gear (31).
 5. The tool turret according to claim 3, characterized in that the base body (1) has a central support column (11) which defines the turret axis (13) and around which the tool disk (7) is pivoted, and that within the latter there is a guide body (55, 61) on which the movable components of the clutch such as the bushing (47) and the output-side gear part (35) which is supported in it are guided both for radial movements between the operating positions and also for the pivoting movements around the turret axis (13).
 6. The tool turret according to claim 5, characterized in that in the second operating position the flattened part (71) of the body of revolution (35) presses through a passage (69) of the guide body (61) onto the flattened end sections (72) of the support column (11) and thus fixes the guide body (61) in its angular position with respect to the turret axis (13).
 7. The tool turret according to claim 1, characterized in that the clutch can be transferred into the operating positions using a hydraulic medium, preferably by means of hydraulic actuation.
 8. The tool turret according to claim 2, characterized in that the bushing (47) on the outer peripheral side has a projecting ring body (53) which as a movable annular piston separates from one another the pressure chambers (57, 59) which are made on the guide body (61) in the guide section (55) on which the bushing (47) for the displacement motions between the operating positions is guided, and that the pressure chambers (57, 59) can be selectively supplied with hydraulic medium.
 9. The tool turret according to claim 5, characterized in that the drive-side crown gear (31) of the tool drive is mounted on a hollow shaft (25) which surrounds the support column (11).
 10. The tool turret according to claim 1, characterized in that the drive for the rotary motions of the tool disk (7) around the turret axis (13) is a torque motor (21) which is located coaxially to it and whose outer rotor (19) is connected to the tool disk (7) for its direct driving.
 11. The tool turret according to claim 9, characterized in that to fix the rotary position of the tool disk (7), there is a clamping mechanism (15) between the base body (1) and the tool disk (7). 